Distributor



June 25, 194.6. 1'. H. CLARK 2,402,503

` DsTRzBUToR Filed March 2.3, 1944 2 Sheets-Sheet 1 INVENTOR. rfPfL/o/P H. CA4P/f 47' 1PA/IY June 25, 1946. T. H. CLARK DISTRIBUTOR .Filed Maron 1s. 1944 2 Sheets-Sheet 2 JNVENTOR. 76E-TUI? 0IA/Pl( Patentedl June 25, 1946 DISTRIBUTOR Trevor H. Clark, New York, N. Y.,'assignor to'Federal Telephone and Radio Corporation, New York, N. Y., a corporation of Delaware Application Mnl-ch 13, 1944, serial No. v526,290

unit and a plurality of contact brushes is usedto transform a direct current current.

However, certain objectionable featureshave been found to be presentI in distributors wherein brushes of carbon or the like are employed.

Due to the constant pressure needed to maintain the proper contact between the brushes and the rotary member an over-abundance of fricintoan alternating v tion is produced. This friction causes the brushes to wear away depositing certain amounts of their 4material upon the surface of the resistor unit and causing untold amounts of disturbances.

If the contacting surfaces of the brushes or the resistor are of an uneven character, arcing yoccurs and sets up disturbing noises in all of the circuits within range of the distributor. It has 9 Claims. (Cl. 179-1715) source of voltage, e. g. an alternating voltage,

v is applied to the conductor bars. a voltage drop also been found that if the material worn away from the brushes remain deposited upon the surface of the resistor unit the resistive quality of the resistor unit will become ineil'ective and an improper distribution will result.

One of the objects of this invention is to produce a distributor which will be devoid of all such objectionable features as stated above.

A further object is to produce a simple and inexpensive distributor for the proper distribution of current. v

A still -further object is* to produce a distributor wherein the distribution of current is accom? plished by capacitive relation of the elements therein. A

A still further object is to produce a distributor wherein the proper output for a given input will be maintained at all times.

A still further object is to produce a distributor wherein capacitive electrodes may be employed.

One of the features of my invention is to produce a distributor provided with a housing having a rotary disk' therein.` Mounted upon said disk is a resistor unit having conductor lbars overlying oppositely disposed edges and connected to a pair of spaced apart conductor rings. Also mounted within said housing are a plurality of electrodes or condenser plates in capacitive relation to the surface of said resistor unit. If a is produced in said resistor. Accordingly adjustment of said electrode toward or away from each other or relative to the conductor bars will vary the voltage drop from points on the resistor unit opposite the electrodes to theV conductor bars. By use of means for creating relative rhythmic movement, such as rotary movement, between the electrodes and the resistor unit while maintaining them in capacitive. relation a radio frequency envelope modulated in amplitude at the speed of lthe relative movement and devoid of noises or fluctuations of the amplitude will be produced. A still further feature lies in the provision of a second pair of electrodes to produce a second envelope. Angular v adjustable means may be provided forthe first and second electrode pairs to permit adjustment of the phase of both envelopes in accordance with the angular position of the two pairs of electrodes. A still further feature lies in the provision for mounting still another pair cfbrushes in capacitive relation to the conductor rings to transfer energy to or from the resistor unit without the use of sliding contacts.

Further and ancillary objects and features of lowing description and drawings wherein:

Fig. 1 is a front elevational view partly shown in section of a structure embodying the principles of my invention;

Fig. 3 is a vertical section taken along the lines 2-2 of Fig. `1;

Fig. 8 is a rear elevational view ture shown in Fig. 1:

Fig. 4 illustrates plan views of modined forms of capacitor electrodes that may be employed in of the strucmy distributor; and

Figs. 5, 6, 7, 8 and 9 are schematic circuit diagrams showing applications of my invention.

Referring now to Figs. i, 2 and 3, there is shown a distributor I havlnga split housing 2-2a provided' with insulated cover plates 3 and l, Cover v center of said cover plate is also provided with a cylindrical opening i adapted to receive a depending portion ll of an auxiliary cover l2. This auxiliary cover is provided with slotted openings I3 having raised edge portions I6 to accommodate the square Shanks I6 of capacitor electrodes |`in an adjustably fixed position. Near the remote ends'-oI said raised edge portions of the slotted openings l: there are provided clamping screws l1 to maintain the capacitor electrodes l5 in an adjustably xed position with respect to one another and in proper capacitive relation Ato the surface of the rotatable resistor. The auxiliary cover also has provided near its outer periphery arcuate slots I8 concentric to the axis of rotation for the rotatably adjustable movement of said auxiliary cover with respect to said cover plate 3 and consequent rotary adjustment of electrodes I5 with respect to electrodes 6, and held in adjustably fixed position by locking screws IB.

Mounted within the casing Z-ia is a rotatable disk 2|] of dielectric material provided with a gear 2 l, ball races 22 and adapted to be rotated by anotherA gear 23 driven by a motor M adjacent the outside of the distributor.

imbedded in the face 2lla of the disk 2U is a dat plate or layer 2E of resistive material, for example, carbon or the like, whose four edges are couidistant from the geometrical center of said disk and so proportioned to have a linear voltage drop between any two spaced points. Also embedded in the same face of disk 20 are two conductive bars 24, 25, overlying the oppositely disposed edges of resistor plate 2B the lengths of each of the oonductor bars being substantially the length of any one edge of the fiat plate 26. This fiat resistor plate and the conductor bars together form 'the complete resistor unit of the distributor and may be fastened into the disk in any well known manimbedded in the opposite face 2Gb of the disk 20 are two spaced apart collector rings 2l, 2B of conductive material positioned concentrically to each other and the axis of rotation. The outer ring 21 is connected electrically to the conductor bar 24 while the inner ring I8 is connected electrically to the conductor bar 25. Mounted on the inner face of the cover 4 are two capacitor electrodes 29, 30 adjustably mounted to provide a capacitive coupling between said electrodes and the surface of collector rings 21, 28, the Shanks of the electrodes providing electrical terminals on the outer surface of said cover 4.

Instead of collector rings 21 and 2B and their pick-up electrodes 29 and 3U, for capacitively coupling the rotor and stator of my novel device,

inductive coupling means may be employed, as

shown in Figs. 5 and 6. One winding, we, of transformer 4l) is connected across the resistor 40 and the other winding, 40h, is connected to exterior or output terminals of the device. Winding 40a may be given a conventional pancake form and its turns imbedded in or carried on the face 2Gb of disc 2l) in the manner suggested for the rings 21, 28 in Figs. l and 2, the two ends of the winding being passed through the disc and con nected to bai-52| and 25. The stationary winding All@ 4 Mib, carried on plate l would preferably also be of the pancake type for close coupling with the rotating winding, the two windings being carefully positioned concentrically with the axis of ro tation to eliminate variations in coupling as the disc 2U turns.

-'I'he structure described above may be used to amplitude modulate an alternating current or voltage wave, the envelope of the modulated wave having undulations determined by the relative rotation of the resistor and the electrodes capacitively coupled thereto. A few examples of this unit applied to circuits for producing the desired converting distribution are shown in Figs. 5, 6, '1 and 8.

As shown in Fig. 5 a source of alternating voltage is connected to capacitor electrodes 5. This connection produces a voltage difference between electrodes E and conductor bars 24 and 25. Because of this potential difference and the capacitive coupling current from source 5D is applied to conductor bars 24 and 25 and over rotary transformer Ml to a utilisation circuit. Relative rotation between the resistor 2E and electrodes t causes variation in the potentialdrop in resistor 26 between points on the resistor surface opposite the electrodes andconductor bars 24 and 25. This variation in potential drop causes changes in the amplitude of the output current to the utilization circuit at a. frequency determined by the rate 4of the relative rotation.

The circuit Shown in Fig'. d is substantially that shown in Fig. 5. Howe-ver, instead olE the source 5i] being connected to electrodes it is now connected to the stationary coil ci the rotary trims former Ml, As the rotary transformer is inductiveiy coupled energy will be transmitted therefrom to the utilization circuit over the conductor bars LM and resistor it, then by capacitance to the electrodes t. Here again the relative rotation of the resistor 2t together with conductor bars 24 and 25, will cause a variation in the potential drop in the utilization circuit, connected to the electrodes (i. and the changes ln the i current amplitude to the Autilizatimfi circuit at a frequency determined by the rate of relative rotation.

The circuit shown in Fig. 7, although similar in most respects to Fig. 5, diilers only in the fact that the output of the source 50 alter being transferred capacitively by the electrodes B to the resistor 25 and its accompanying conductor hars 24 and 25 is capacitively transferred to the utilization circuit. This is accomplished by connectinf,7

` the conductor bars 2l and 25 of the resistor 2G respectively to a pair of conductor rings 28 and 25 which are positioned concentric to the axis of rotation of the resistor 2E. A pair of electrodes 29 and 30 capacitively transfer the current from the conductor rings 2S and 28 to the utilization circuit. Here again as in Fig. 5 the same potential drop oi current from source 5U to the utilization circuit will take place, andthe same changes ln current amplitude at a frequency determined by the rate of relative rotation.

The circuit shown in Fig. 8 differs from Fig. 7 only in the fact that the source of power 5D is connected to the electrodes 25 and 30 instead of electrodes 6. The transfer of the current from source 50 to the utilization circuit is now reversed, but the conditions within the utilization circuit will have the same potential drop and the same changes in current amplitude as in Fig. 1.

Should there be a requirement for advancing or retarding `the capacitor electrodes 5, as a unit,

accesos 5 this could be accomplished by simply loosening the screws 3b and rotatably adjusting the cover plate 3. If for any reason whatsoever the adevancing or rotar-ding of one set ofV capacitor electrodes relative to the other set is required, this vcould be accomplished by simply loosening the locking screws I9 in the auxiliary cover i2.

Many uses or applications of my invention can be envisioned, either separately or in combination' 7 between the modulating waves in the two circuits lof the two pairs of electrodes.

When a source of current is fed to the resistor unit and by capacitance transferred to one pair of electrodes connected to oppositely disposed 'deflection plates in an oscilloscope, a linear sweep wili be pro duced across the fluorescent screen. A circular 25 sweep can be produced by the use of two pair or the electrodes i5 and 8 placed 90 apart and connected to the four deections elements 6U of the oscilloscope, as shown, by'.way Aoi.' example, in Fig. 9.

Should there be the ecessity of rotating the electrodes instead of the disk and its elements, it would not require much ingenuity to construct a housing wherein this could be made possibleu Nevertheless the relative rotary movement be tween all the elements would not change, but would remain as statedin the appended claims. It is to be clearly understood by those skilled ln this art that the apparatus shown and described herein is only illustrative of my invention and is not to be construed as a limitation on the scope oi' my invention as set forth in the objects and appended claims.

Iclaim:

1. A capacitive distributor comprising a resistor d6 unit having a resistance distributed over a given area to provide a resistor surface, a rst pair of terminals, means for coupling said first pair oi terminals in capacitive relation to said resister surface, means for producing relative rotary movement between said resistor unit and said rst pair of terminals. a second pair of terminals..

and means for coupling said second pair of ter minals to spaced points on the perimeter of said resistor unit. l

' 2. A. capacitive distributor according to claim 1, further comprising a source of alternatins current connected to one o1' said pairs ol' termlnals, and a. utilization circuit connected to the remaining pair of terminals.

3. A capacitive distributor comprising a resistor unit having a resistance distributed over Aa givin area to provide a resistor surface,l a ilrst pair of terminals, means for coupling said first pair of terminals in capacitive vrelation to said resistor surface, means for producing relative rotary movement between' said resistor unir and said rst pair of terminals, a pair of spaced apart conductor rines connected to spaced points on the perimeter of said resistor unit, aseeond pair of terminals and means for capacltlvely coupling said pair of conductor rings tosaid second pair of terminals.

4. A capacitive distributor comprising a resistor unit having a resistance distributed over a given area to provide a resistor surface, a first pair of terminals means for coupling said first pair of terminals in capacitive relation to said resistor surface, means for producing relative rotary movement between said resistor unit and said rst pair of terminals, a pair of conductor bars overlying oppositely disposed perimeter edges of said resistor unit, a second pair of terminalaand means for lcoup-ling said conductor bars to said second pair of terminals. y

' 5. In a capacitive distributor, the combination of a housing', a disk of substantiallycircular conilguration mounted within' said housing, a resistorunit mounted on said disk having a re sistance distributed over a given area, to provide a resistor surface, a rst'pair of capacitor elec@l trodes mounted within said housing in capacitive relation to the surface'of said resistor unit, a j 'pair of spaced conductor rings mounted on and concentric to the 'axis' of said disk and connected to spaced points on theperimeter of said resistor mult, and a second pair of capacitor electrodes mounted within said housing in capacitive relation to said conductor rings.

6; In a capacitive distributor according to claim 5, further comprising means for producing a rel-y ative rotary movement between said resistor unit and said conductor on Aone hand, and said first pair and said second pair of capacitor electrodes on the other.

7. In a capacitive distributor, the combination of a housing, a disk of substantially circular con..

figuration mounted within said housing,- a'resister unit mounted on saidl disk having a resistance distributed over a given area to provide a resistor surface, a pair of conductor bars overlying oppositely disposed perimeter edges of said resistor unit, a first pair of capacitor'electrodes mounted within said housing in capacitive relation to the surface of said resistor unit, a second pair of capacitor electrodes 'mounted Within said housing, means for capacitively coupling said pair of conductor bars to saidecondpair of capacitor electrodes, and means for producing relative rotary movement between said resistor' unit and said pair of conductor bars on one hand, and said first pair and said secondl pair ot electrodes on the other, said coupling means including a, pair of spaced apart conductor rings respectively connected to said overlying pair oi' conductor bars and concentric tosaid disk.

8. In a capacitive distributor, the combination yof a resistor having an extended resistance surface, terminals lconnected to vspaced points on said resistance surface, a condenser plate mounted in spaced capacitive relation `with said surface, saidplate being movable over said surface to vary the distance between said plate and said points.

9. In combination, a resistor having an ex tended resistance surface, a capacitor electrode mounted in capacitive relation to'said resistance surface, electrical connections to spaced points on said resistance surface, means for rhytnmically moving said capacitor electrode over said surface.

' .'rnsvoa H. CLARK. 

